1. Field of the Invention
This invention relates to detergent pouch construction of a type for ensuring full disposition of the detergent content of the pouch into the laundry liquor.
Water sensitive fibers are formed into a web or sheet. The interfiber spacing is selected such that laundry detergent particles are contained by the web or sheet. When the detergent containing pouch made of the web or sheet is wetted, the fibers loose a predetermined crimp. The length of fiber between bonding sites increases and the interstices enlarge. The detergent contained within the pouch can then pass through into the laundry liquor.
2. Description of the Prior Art
Many users of automatic laundry machines prefer to use pouches of detergent because such provides ease of use, reduces waste of detergent by providing a pre-measured amount of detergent compatible with the capacity of the average washing machine, while also eliminating contact of the detergent with the hands of the user, and facilitates general neatness of the laundry area.
However, in the past, various difficulties have arisen with the pouches of the prior art since the fabric of some pouches fail to hold detergent powder therein, while others have openings too small to allow for full passage of the detergent into the washing liquid.
U.S. Pat. No. 4,188,304 discloses the use of laundry pouches having water sensitive side seals which cause the construction to open at one or more seams when immersed.
In another U.S. Pat. No. 4,555,354, there is taught the use of mechanically weak seals which become unsealed due to the agitating action of the washing machine. Rough handling of this product during transportation and merchandising can lead to failure of the seals prematurely.
U.S. Pat. No. 4,348,293 relates to water soluble sheets or coatings adhered to the porous non-woven substrate which, when dissolved, permit the transport of the detergent powders through the intersticed spacings.